It would cost me around $250, is it worth it?
Will it be able to handle it all? Would it be able to handle Jellyfin transcoding if necessary?
I actually run a HP 800 G3 tower I needed the 5 1/2 drive bay for my blue-ray drive, with a i7-7000 it will do fantastic, mine runs my NAS. Jellyfin, Hand break, and Makemkv in containers doesn’t have any issues can handle 3-4 streams with no issues
Yes, it’s plenty. My own “most powerful” server runs on an i7-7700, and I’ve never seen it’s CPU usage spike above 20%.
Intel 14nm CPUs are still solid performers for secondary usage today, mostly because Intel stuck with that process for so long. Even their newest processors on the 10nm process is essentially just a die shrink version of the 14nm process, because that’s how Intel insists on working.